High burst closure assembly for large packages

ABSTRACT

The present disclosure relates to a high burst closure which allows for bottom filling of packages, such as large bags, and further provides increased resistance to damage from the dropping or shock loading of the filled package. This is achieved by providing profiles that combine an upper portion of one profile and its related flange, so as to form a juncture above a peel seal joining one profile to the other, so that external forces on a package or bag from bottom filling or shock loading are directed toward the juncture thereby causing a shear force against the peel seal or other frangible connection, thereby increasing the resistance of the package to external forces.

This application is a continuation-in-part of application Ser. No.11/728,477 filed Mar. 26, 2007 entitled “High Burst Zipper Assembly forLarge Reclosable Packages” which claims priority under 35 U.S.C. §119(e)from provisional application Ser. No. 60/839,447, filed on Aug. 23,2006, entitled “High Burst Slider Zipper for Large Bags and Method ofManufacture”, the contents of which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to closure assemblies for packages whichare large bags, particularly closure assemblies which achieve high burststrengths while allowing an easy-to-open configuration, and the methodsfor manufacture thereof.

2. Description of the Prior Art

Large packages, bags or pouches, such as those used for pet food,charcoal, cat litter and similar items are typically filled and sealedshut. These packages may be formed by form fill and seal (FFS) or byother methods. Prior attempts to incorporate an easy to use closuremechanism have been unsatisfactory due to the unique requirements of alarge bag with a relatively heavy load. In particular, filling from thebottom places all of the load on the closure during filling. This loadcan cause the closure mechanism to fail and open. Similarly, dropping afilled bag onto a pallet or similar rough handling duringtransportation, as well as exposing a bag to elevated temperaturesduring transportation, can cause the closure mechanism to fail.

The prior art has addressed these deficiencies by folding over the endof the package, particularly a multi-wall package, using an expensivelabel as tape thereby allowing successful filling and transport.Similarly, the prior art has addressed these deficiencies by using aliner peel seal below the zipper and a solid tear line in the zipperflange to provide a fill and transport system that does not rupture andspill the contents. However, these methods have slow rates ofproduction, as well as increased costs of production, and frequently donot result in a satisfactory product for the consumer.

Some further examples of the prior art which are not entirelysatisfactory are found in U.S. Pat. No. 6,979,482 entitled “MultiwallBag with Zipper and Fin” issued on Dec. 27, 2005 to Hartzell et al. andU.S. Pat. No. 7,090,904 entitled “Enhanced Slider Zipper Multiwall Bagand Associated Methods” issued On Aug. 15, 2006 to Hartzell et al.

Typical prior tamper-evident zipper assemblies are disclosed in U.S.Pat. No. 6,354,738 entitled “Tamper Evident Reclosable Plastic Bag”issued on Mar. 12, 2002 to Buckman et al.; U.S. Pat. No. 4,647,063entitled “Reclosable Bag with Laminated Liner and Method” issued on Jan.13, 1987 to Sullivan; and U.S. Pat. No. 5,509,735 entitled “ClosureArrangement Having a Peelable Seal” issued on Apr. 23, 1996 to May.

OBJECTS AND SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a closureassembly for packages, particularly large bags, formed by form fill andseal or other methods, which provides for high burst strength in bottomfilling or top filling configurations, to allow the bags to withstanddropping or shock loading without the closure mechanism bursting open,while allowing for an easy to open configuration.

It is therefore a further object of the present invention to providesuch a closure assembly without significant increases in manufacturingand related costs.

It is therefore a still further object of the present invention toprovide a method of manufacture for a product achieving the aboveobjects.

These and other objects are attained by providing a closure assembly forpackages, particularly large bags, with a first profile with a firstupper separating portion, a first flange, and an interior flange, and asecond profile with a second upper separating portion and a secondflange. A peel seal is formed between the lower end of the interiorflange and a generally central portion of the second profile. Thiscauses the external forces on a bag from bottom filling or shock loading(or forces from within the bag, typically created when the bag isdropped on its top or side) to be directed towards the junction of theinterior flange and the first upper portion, thereby redirecting thepeel seal from a peel position to a shear position. As the forcerequired to separate a peel seal in a shear position is several timesgreater than the force required to separate the peel seal in a peelableposition, the load-bearing capacity of the package or bag is increasedto meet the requirements previously mentioned.

These and other objects are similarly obtained by providing a closureassembly for a package, particularly large bags, wherein one of theflanges is provided in two segments in a T-configuration, with theintersection of the two segments being above the peel seal.

These and other objects are similarly obtained by providing a closureassembly for a reclosable package, particularly large bags, with aflange connected to the profile above the peel seal.

DESCRIPTION OF THE DRAWINGS

Further objects and advantages of the invention will become apparentfrom the following description and from the accompanying drawings,wherein:

FIG. 1 is a plan view, partially in phantom, of a typical reclosablepackage incorporating the zipper assembly of the present invention.

FIG. 2 is a cross-sectional view along the upper portion of plane 2-2 ofFIG. 1, showing the cross section of the zipper assembly of the presentinvention.

FIG. 3 is a cross-sectional view along the upper portion of plane 2-2 ofFIG. 1, showing the cross section of an alternative embodiment of thezipper assembly of the present invention. Additionally, an alternativearea of detail is shown with a variation of the alternative embodiment.

FIG. 4 is a cross-sectional view along the upper portion of plane 2-2 ofFIG. 1, showing a cross section of a portion of the package or bag in anunstressed configuration.

FIG. 5 is a cross-sectional view along the upper portion of plane 2-2 ofFIG. 1, showing a cross section of a portion of the package or bag whenan internal load (i.e., a force from within the package or bag) isapplied thereto.

FIG. 6 is a cross-sectional view of the upper portion of plane 2-2 ofFIG. 1, showing a cross section of a portion of the package or bag andfurther showing the resultant forces on the zipper assembly when aninternal load is applied to the package or bag.

FIG. 7 is a cross-sectional view of a first alternative embodiment ofthe zipper.

FIG. 8 is a cross-sectional view of a second alternative embodiment ofthe zipper.

FIG. 9 is a cross-sectional view of a third alternative embodiment ofthe zipper showing the use of reinforcing ribs on one profile.

FIG. 10 is a cross-sectional view of a fourth alternative embodiment ofthe zipper showing a tamper-evident removable hood.

FIG. 11 is a cross-sectional view of a fifth alternative embodiment ofthe zipper, which substitutes a secondary zipper-type assembly for thepeel seal.

FIG. 12 is a cross-sectional view of the fifth alternative embodiment ofthe zipper, shown in a loaded position thereby putting the secondaryzipper-type assembly into a shear configuration.

FIG. 13 is a cross-sectional view of the zipper profile, prior toattachment to the package or bag walls, and further prior to thestomping of the ends and the insertion of the sliders.

FIG. 14 is a perspective view of the zipper profile, prior to attachmentto the package or bag walls, and further prior to the stomping of theends and the insertion of the sliders.

FIG. 15 is a plan view of the vacuum device used to spread the flangesof the zipper prior to the adhesive insertion step.

FIG. 16 is a cross-sectional view of glue or similar adhesive beinginserted onto the interior of the flanges of the zipper.

FIG. 17 is a schematic of the processing of the packages or bags afterthe zipper has been attached.

FIGS. 17A and 17B are alternative plan views of the sealing of theflange ends of FIG. 17.

FIG. 18 is a plan view of the reclosable package or bag with the zipperattached thereto.

FIG. 19 illustrates a first alternative for manufacturing the zipper.

FIG. 20 illustrates a second alternative for manufacturing the zipper.

FIG. 21 illustrates a third alternative for manufacturing the zipper.

FIG. 22 is a cross-sectional view of a first alternative top-fillingembodiment of the zipper.

FIG. 23 is a perspective view of the walls of the package, with stripsof polyethylene, in preparation for the second alternative top-fillingembodiment of the zipper, as shown in FIG. 24.

FIG. 24 is a cross-sectional view showing the second alternativetop-filling embodiment of the zipper attached to the package walls.

FIG. 25 is a cross-sectional view showing the third alternativetop-filling embodiment of the zipper attached to the package walls.

FIG. 26 is a cross-sectional view showing the fourth alternativetop-filling embodiment of the zipper attached to the package walls.

FIG. 27 is a cross-sectional view of a first embodiment of a high burstclosure without a zipper.

FIG. 28 is a cross-sectional view of a second embodiment of a high burstclosure without a zipper.

FIG. 29 is a cross-sectional view of a third embodiment of a high burstclosure without a zipper.

FIG. 30 is a cross-sectional view of a first variation of the attachmentof a high burst closure to package or bag walls.

FIG. 31 is a cross-sectional view of a second variation of theattachment of a high burst closure to package or bag walls.

FIG. 32 is a cross-sectional view of a third variation of the attachmentof a high burst closure to package or bag walls.

FIG. 33 is a cross-sectional view of a fourth variation of theattachment of a high burst closure to package or bag walls.

FIG. 34 is a cross-sectional view of a high burst closure, including ahandle structure as a bag wall extension or similar structure.

FIG. 35 is an alternative cross-sectional view of a high burst closure,including a handle structure.

FIG. 36 is an alternative cross-sectional view of a high burst closure,including a handle structure implemented as a flange extension.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings in detail wherein like numerals indicatelike elements throughout the several views, one sees that FIG. 1 is aperspective view of a typical reclosable package 100, such as a largebag, which incorporates the zipper assembly 10 of the present invention.Reclosable package 100 may be formed by form fill and seal or by othermethods. Reclosable package 100 includes a front wall 102 and a rearwall 104. Front and rear walls 102, 104 may be separate polymeric ormulti-sheet panels sealed together at edges 106, 108. Alternatively,front and rear walls 102, 104 may be provided as a single tube with orwithout a lap seal in the longitudinal direction. Front and rear walls102, 104 may be formed from virtually any substrate in the packagingart—laminate films, plain polyethylene or polypropylene films,multi-wall paper, and polypropylene woven layer bags or any combinationor hybrid thereof. Additionally, gussets (not shown) may be providedbetween front and rear walls 102, 104 at edges 106, 108, or similarly atbottom 110.

Bottom 110 may be sealed shut, or folded over and then glued. Reclosablepackage 100 is typically bottom filled, so that the seal or glued foldmay be formed after filling. However, other methods of filling, such astop filling before the complete application of zipper assembly 10, areequally applicable to the present invention and are disclosed herein.

A longitudinal seal or seam 111, which can be a lap or fin seal or seam,may optionally be formed in a generally central longitudinal location onrear wall 104 and is shown in phantom on FIG. 1.

Mouth 112 is formed at the top of the reclosable package 100 of FIG. 1,and is reclosably sealed by zipper assembly 10.

As shown in FIGS. 1 and 2, zipper assembly 10 is formed from polymericmaterials and includes first profile 12, second profile 14 and optionalslider 15 (see FIG. 1). First profile 12 includes first interlockingelement 16 and first flange 18. Similarly, second profile 14 includessecond interlocking element 20 and second flange 22. Optional slider 15is mounted on first and second profiles 12, 14 and operates in aconventional manner by interlocking first and second interlockingelements 16, 20 of respective first and second profiles 12, 14 whenmoved in a closing direction and separating first and secondinterlocking elements 16, 20 of respective first and second profiles 12,14 when moved in an opening direction.

Peel seal 24 is formed between central locations of first and secondflanges 18, 22. Peel seal 24 may be replaced by other frangible (andtherefore tamper-evident) seals, or even a rip-cord (eithersupplementing or substituting for the peel seal 24). Peel seal 24 ismore resistant to shear forces than to peeling forces. Peel seal 24, orany substitutes therefor, particularly when loaded in a shearconfiguration, is typically sufficiently strong to support the loadsrequired by bottom filling. Peel seal 24 is typically pre-activated, butmay be activated at the time of package or bag conversion. Additionally,first flange 18 in FIG. 2 includes upward fold 26 immediately orproximately below peel seal 24. First flange 18 continues upward fromupward fold 26 to downward fold 28, wherein hard seal 30 is formedbetween a portion of first flange 18 above peel seal 24. Thisconfiguration can be considered to divide first flange 18 into threeportions—first portion 34 which extends from first interlocking element20 to upward fold 26, second portion 36 which extends from upward fold26 to downward fold 28, and third portion 38 extends from downward fold28 to first distal end 40 thereby providing an area for sealing, gluing,or otherwise securing to front wall 102 of package 100. Likewise, secondflange 22 extends from second interlocking element 20, past peel seal24, to second distal end 42 thereby providing an area for sealing,gluing, or otherwise securing to rear wall 104 of package 100. As shownin FIGS. 1, 4, 5 and 6, first and second flanges 18, 22 are typicallysealed, glued or otherwise secured to the upper exterior surfaces offront and rear walls 102, 104. However, some embodiments may seal, glueor otherwise secure first and second flanges 18, 22 to upper interiorsurfaces of respective front and rear walls 102, 104.

In the alternative embodiment of FIG. 3, second portion 36 of firstflange 18 is omitted, so that first and third portions 34, 38 areseparate sheets or segments of web. Third portion 38 is joined to agenerally central location of first portion 34 by hard seal 30.Alternatively, hard seal 30 can be omitted if first and third portions34, 38 are formed integrally and simultaneously by extrusion, as shownin the alternative area of detail of FIG. 3.

In the configuration of either embodiment, as shown in FIGS. 5 and 6,the external forces on package 100 from bottom filling or shock loading(or forces from within the bag) are directed toward hard seal 30 (whichis above the peel seal 24) and redirected so as to cause a shear forceon peel seal 24. As a peel seal is much more resistant to a shear forcethan a conventional peeling force, the resistance of package 100 toexternal or internal forces is greatly increased.

FIGS. 7 and 8 disclose embodiments, wherein first flange 18 isrelatively short, extending from profile 16 and terminating upwardlyadjacent to gap 25. First flange 18 is sealed or otherwise joined toextension segment 46 at point 50. Second flange 22 includes proximalsegment 21 which extends from profile 20. Second flange 22 furtherincludes distal segment 23 which is joined to proximal segment 21 atfold 44 wherein a line of weakness, such as a perforated or scored line,is provided in order to provide additional tamper evidence afteropening. Distal segment 23 extends upwardly from fold 44 and terminatesdownwardly adjacent to gap 25. Second flange 22 is sealed or otherwisejoined to extension segment 48 at point 52 and distal segment 23 issealed or otherwise joined to first extension segment at point 54 andadjacent to peel seal 24. The connections at points 50, 52, 54 aretypically formed by heat sealing. Peel seal 24 is further formed betweenfaces (or facing portions) of proximal segment 21 and distal segment 23.

Extension segments 46, 48 are typically formed with nominal 6 mil film,but those skilled in the art will recognize a range of equivalents afterreview of this disclosure. Extension segments 46, 48 are joined,typically by adhesive, to front and rear walls 102, 104, respectively.The embodiment of FIG. 7 differs from that of FIG. 8 in that theextension segment 48 of FIG. 8 includes fold 56 between inner portion 57and outer portion 59. Inner portion 57 is sealed to second flange 22 atpoint 52 while outer portion 59 descends past flanges 18, 22.

The alternative embodiment of FIG. 9 includes reinforcing ribs 60 onflange 22 to increase the stiffness of flange 22. The alternativeembodiment of FIG. 10 (based on the construction of FIG. 3) includestamper-evident header 62 formed of film enclosing zipper assembly 10.Tamper-evident header 62 includes lines of weakness 64, 66, typicallyformed by a perforated or scored line, in order to provide access tozipper assembly 10.

The alternative embodiment of FIG. 11 (unloaded) and FIG. 12 (loaded)substitutes the separable connection of secondary zipper 27 for theseparable connection of peel seal 24 of the previous embodiments.Secondary zipper 27 includes first interlocking profile 29 attached orsealed to first flange 18 and second interlocking profile 31 attached orsealed to second flange 22. As shown in FIG. 12, the loadedconfiguration, or other forces from within the package 100, causes ashear force to be applied to secondary zipper 27. Secondary zipper 27,similar to peel seal 24, resists a shear force to a much greater extentthan a peeling force thereby increasing the strength of the resultingpackage when in the loaded configuration of FIG. 12. The possibility ofthe substitution of the secondary zipper 27 for the peel seal 24 isenvisioned for all of the disclosed embodiments of zipper assembly 10.

The manufacturing process of reclosable package or bag 100 isillustrated in FIGS. 13-18. A continuous length of interlocked zipperprofiles 12, 14 is illustrated in FIGS. 13 and 14 and is typicallyprovided from a spool 190 (see FIG. 17). The flanges 18, 22 of zipperprofiles 12, 14 are then spread apart, typically by a spreader apparatus192 such as is illustrated in FIG. 15 (also see FIG. 17) wherein theportion of flanges 18, 22 immediately below the interlocked profiles 12,14 is fed into the nip 200 between rollers 202, 204. A portion offlanges 18, 22 extends therefrom and is engaged by vacuum elements 206,208. Vacuum elements 206, 208 spread the portions of flanges 18, 22extending from rollers 202, 204 so that adhesive, typically a hot-meltreactive adhesive such as a hot melt, cross-linkable adhesive(particularly, a hot melt cross-linkable polyurethane reactiveadhesive), can be applied or otherwise placed by nozzle 210 onto theinterior of flanges 18, 22 as shown in FIG. 16 (those skilled in the artwill recognize that some adhesives should be applied by a downwardlypointing nozzle 210 with the orientation of the flanges 18, 22 duringadhesive application changed in accordance therewith). Additionally,optional plasma or corona discharge station 209 may change the surfaceenergy (described later in detail herein) of the flanges 18, 22 prior toapplication of adhesive. The flanges 18, 22 are temporarily clamped byclamps 194 (see FIG. 17), or pressure similarly applied, to the outsidebag walls 102, 104 of successive packages or bags 100 (typicallysupplied with an open bottom and free of contents).

The adhesive layer is typically applied to flanges 18, 22 in a pathdivergent or parallel to the bag supply so that the flanges 18, 22 aresubsequently guided from the divergent or parallel path to a positionwherein the bag walls are captured within the flanges 18, 22.

Zipper 10 is stomped at stomp locations 68 at package-width intervals,typically two stomps 68 at a time, by stomper 220 and slider 15 isinserted therebetween by slider inserter 222 as shown in FIG. 17. Thelaterally extending excess portions of the flanges are heat sealed,glued, or ultrasonically bonded to each other by bonding station 224.

FIG. 17A illustrates a possible configuration for the flanges 18, 22 tobe sealed to each other in an inverted T-shaped area 400 below end stomp68 between successive bags 100 by bonding station 224. FIG. 17Billustrates a possible configuration for the flanges 18, 22 to be gluedto each other in rectangular area 402 between edges of successive bags100 and below end stomp 68.

The zippers are then cut at cutting station 226 to achieve the package100 illustrated in FIG. 18 (with the phantom lines illustrating a gussetbetween the front and rear walls). The resulting packages or bags 100are typically unfilled and have an open bottom. Optional filling station225 is illustrated prior to cutting station 226. Optional fillingstation 225 may be top filling (in which case, zippers such asillustrated in FIG. 22 or 24-26 may be used) or bottom filling (in whichcase, the packages or bags are inverted and a bottom sealer is includedwith the filling station 225). However, separate subsequent fillingsteps may be performed at a different location to fill packages or bags100 with contents and seal the bottom 110 of the package or bag 100.

Alternative embodiments may cut the zippers prior to the application ofthe adhesive, may include pre-mounted sliders, or sliders inserted andstomps formed prior to the gluing process. Walls 102, 104 may be foldedto form gussets prior to the securing of the zipper assembly 10 thereto.Similarly, gussets may be attached below or within the flanges 18, 22 byglue dots or similar connection methods. To reinforce the gussetsunderneath the zipper assembly 10, glue may be applied in between theinside faces of the gussets or in between the outside faces of thegussets.

FIGS. 19, 20 and 21 illustrate variations in the formation of the zipperassembly 10. FIG. 19 illustrates how first and second sheets of web 300,302 can be joined by peel seal 24, a fold 28 formed in second sheet ofweb 302 and then sealed to first and second flanges 18, 22 therebyachieving a construction similar to FIG. 2. Similarly, FIG. 20illustrates first and second profiles 12, 14 being joined by peel seal24 and first sheet of web 300 being slit into two pieces which aresealed to flanges 18, 22 thereby forming a construction similar to thatillustrated in FIG. 3. In FIG. 21, a lower portion of first flange 18 isremoved and then resealed to an upper portion of first flange 18 therebylikewise forming a construction similar to that illustrated in FIG. 3.Alternatively, first flange 18 can be folded to achieve the constructionof FIG. 2. Further alternatively, the T-shaped configuration of firstflange 18 can be achieved by simultaneous extrusion of a single T-shapedflange.

With respect to the adhesive used by nozzle 210 to fasten the zipperassembly 10 to the walls 102, 104 of package 100, it has been found thathot melt, cross-linkable adhesives (such as hot melt polyurethanereactive adhesive which are cross-linkable) have been found to besuperior to ordinary hot melt adhesives, both for multi-wall paper andwoven polypropylene walls. Likewise, this adhesive has been foundsuperior for the construction of all seams of package or bag 100,including bottom seam 110 and longitudinal seam 111. This was determinedby tests in which the package 100 was loaded with 2.5 times its ratedload and hung upside down (that is, with the load bearing on the zipperassembly 10) and placed in 140 degree Fahrenheit environment (which isrepresentative of temperatures which may be encountered during shipping)for seventy-two hours. The package 100 was considered to have passedthis test if the package 100 maintained its integrity during thisperiod.

Likewise, this test can be performed for the same load (2.5 times ratedload) and period (seventy-two hours) at negative 20 degrees Fahrenheit(−20° F.) for simulation of cold environments which may be encounteredduring transportation and storage in some climates. The hot melt,cross-linkable adhesives (such as hot melt polyurethane reactiveadhesive which are cross-linkable) have likewise been found to besuperior under these tests and can be applied to all seams of packages,with or without a reclosable zipper.

Similarly, it has been found that pre-treatment of the olefin structuresof the walls 102, 104 (particularly if made from woven polypropylene)and zipper flanges, typically by corona discharge or plasma treatment ofthe walls and flanges, improves the adhesion bond of the hot melt,cross-linkable adhesive (such as hot melt cross-linkable polyurethanereactive adhesive) between the walls and zipper flanges, particularlyfor film structures having a non-polar surface energy of less than 40dynes per square centimeter.

Additionally, heat sealing may be effective in instances wherein the bagsurface includes resin binder type inks.

As shown in FIG. 22, in the first alternative top-filling embodiment ofzipper assembly 10, distal ends 40, 42 of respective segment 38 andsecond flange 22 are attached to respective front and rear walls 102,104 prior to the attachment or sealing of segment 38 to first flange 18.Segment 38 is typically a polyethylene strip that is attached by glue tothe bag wall prior to the filling of the package or bag and by a heatseal to flange 18 after the package or bag is filled. This allows thepackage to be filled with contents through the gap or opening 37 betweensegment 38 and first flange 18 prior to the joining or sealing ofsegment 38 to first flange 18. This top filling eliminates the bottomfilling typically associated with many of the other disclosedembodiments.

As shown in FIG. 23, in the second alternative top-filling embodiment ofzipper assembly 10, polyethylene strips 103, 105 are attached to theexterior of front and rear walls 102, 104 immediately adjacent to mouth112. Extension segment 46 is typically heat sealed or otherwise attachedto polyethylene strip 103 prior to filling of the package 100 andextension segment 48 is typically heat sealed or otherwise attached topolyethylene strip 105 after filling of the package 100 to reach theconfiguration shown in FIG. 24. While FIG. 24, as well as FIG. 25, isillustrated with the zipper assembly 10 of FIG. 7, other equivalentzipper configurations could be substituted for this zipper assembly 10,as would be recognized by those skilled in the art after review of thisdisclosure.

FIG. 25 shows a third alternative top-filling embodiment of zipperassembly 10, similar to that shown in FIG. 24, except that extensionsegment 46 is glued to front wall 102, typically by hot melt,cross-linkable adhesive (such as hot melt cross-linkable polyurethanereactive adhesive) 107 prior to filling of the package 100, therebyobviating the need for polyethylene strip 103. After filling of package100 with contents, similar to the embodiment shown in FIG. 23, extensionsegment 48 is heat sealed to polyethylene strip 105 on rear wall 104.

FIG. 26 illustrates a zipper assembly 10, similar to that of FIG. 3,wherein flange 22 and segment 38 are glued or otherwise sealed orattached to front and rear walls 102, 104 prior to the formation of peelseal 24. Peel seal 24 is formed and activated thereby joining first andsecond flanges 18, 22 to each other after the filling of package 100with contents between first and second interlocking elements 16, 20 asshown by arrow labeled as “fill”. This filling may be done by using theslider (see FIG. 1) to separate the first and second interlockingelements 16, 20, filling between first and second interlocking elements,and then using the slider to interlock first and second interlockingelements 16, 20.

FIG. 27 is a cross-sectional view of a first embodiment of high burstclosure 11. High burst closure 11 includes first profile 12 and secondprofile 14. First profile 12 includes first upper separating portion 17and first flange 18, integral with each other, formed from a singlesheet of polymeric web or similar material. First profile 12 furtherincludes interior flange 19 integrally formed with upper separatingportion 17 or attached by a hard seal to the interior surface thereof.Second profile 14 includes second upper separating portion 21 and secondflange 22. First peel seal 24 is formed between the lower end ofinterior flange 19 and a generally central portion of second profile 14.Alternatives for closing first and second upper separating portions 17,21 are shown in FIGS. 31 and 32. In this, as well as the otherembodiments of high burst closures, similar to the previously disclosedzippered embodiments, loads on the package walls or flanges cause ashear force on the peel seal, as shown in FIG. 12, thereby increasingthe load resistance of the closure and the package in order to meet therequired high burst strength.

FIG. 28 is a cross-sectional view of a second embodiment of high burstclosure 11. In this embodiment, the first profile 12 is formed from afirst upper separating portion 17 which extends to first peel seal 24.First flange 18 is sealed to a generally central portion of first upperseparating portion 17. Again, alternatives for closing first and secondupper separating portions 17, 21 are shown in FIGS. 31 and 32.

FIG. 29 is a cross-sectional view of a third embodiment of high burstclosure 11. A single sheet of polymeric web or similar material is usedto form first profile 12. This sheet forms upper separating portion 17and is folded adjacent to a bottom of peel seal 24 and is then sealed toa generally central exterior portion of first upper separating portion17, with the remaining portion of the sheet forming first flange 18.

FIG. 30 is a cross-section view of the first embodiment of the highburst closure of FIG. 27 (equally applicable to the embodiments of FIGS.28 and 29) with the exterior of first and second flanges 18, 22 sealedto the interior of respective first and second bag walls 102, 104.Alternatively, the interior of the first and second flanges 18, 22 canbe attached by adhesive or other means to the exterior of bag walls 102,104.

FIG. 31 is a cross-sectional view of the first embodiment of the highburst closure of FIGS. 27 and 30 (equally applicable to the embodimentsof FIGS. 28 and 29) wherein second peel seal 31 is added between firstand second upper separating portions 17, 21 so that first and secondupper ends 17′, 21′ of respective first and second upper separatingportions 17, 21 protrude therefrom thereby providing grips for the userto grasp and peel apart the first and second peel seals 24, 31 in orderto open closure 11.

FIG. 32 is a cross-sectional view of the first embodiment of the highburst closure of FIGS. 27, 30 (equally applicable to the embodiments ofFIGS. 28 and 29) wherein the first and second upper ends 17′, 21′ ofrespective first and second upper separating portions 17, 21 are sealedtogether by hard seal 29. Furthermore, first and second lines ofweakness 33, 35 (typically formed by perforated lines or scored lines)are formed in respective first and second upper ends 17′, 21′ under hardseal 29 whereby a user opens closure 11 by grasping an area proximate tohard seal 29 and tearing along the first and second lines of weakness33, 35 thereby removing the resulting header-like portion of first andsecond upper ends 17′, 21′ above the first and second lines of weakness33, 35 thereby gaining access to first peel seal 24 which is opened bythe user by further separating first and second upper separatingportions 17, 21.

FIG. 33 is a cross-sectional view of an embodiment similar to that ofFIG. 28 wherein first wall 102 extends upwardly and is sealed directlyto the generally central portion of first upper separating portion 17,thereby fulfilling the function of first flange 18. Identical to theconfiguration of FIG. 32, first and second upper separating portions 17,21 are sealed together by hard seal 29 and first and second lines ofweakness 33, 35 are formed in respective first and second upper ends17′, 21′. Alternately, a second peel seal, as shown in FIG. 31, canreplace hard seal 29, or the first and second supper ends 17′, 21′ canremain unsealed as shown in FIG. 30.

FIG. 34 is a cross-sectional view of an embodiment similar to that ofFIG. 31 wherein first flange 18 is sealed to first bag wall 102 andfirst bag wall 102 extends above closure 11 and includes aperture 37which serves as a handle. In other words, aperture 37 is formed in aportion of first bag wall 102 which extends above first flange 18.Alternately, first bag wall 102 can be integral with first flange 18(i.e., first bag wall 102 sealed directly to first upper separatingportion 17 thereby eliminating the need for a separate first flange 18)and a separate bag wall extension is sealed to the exterior thereof andaperture 37 formed in this separate bag wall extension.

FIG. 35 is a cross-sectional view of an embodiment similar to that ofFIG. 32 wherein first bag wall 102 extends above closure 11 and includesaperture 37 which serves as a handle. Furthermore, second peel seal 31is formed between first upper separating portion 17′ (proximate to hardseal 29) and first bag wall 102 (downwardly adjacent from aperture 37).

FIG. 36 is a cross-sectional view of an embodiment similar to that ofFIG. 32 wherein an extension 41 of upper separating portion 17 isprovided, with an aperture 43 serving as a handle. This is equallyapplication to upper separating portion 21, or both upper separatingportions 17, 21. Likewise, extension 41 may be implemented incombination with, or in lieu of, the upward extension of first wall 102illustrated in FIG. 34 and the aperture 37 formed therein.

Those skilled in the art will recognize a broad range of possiblecontents for the packages 100, including, but certainly not limited to,charcoal, pet food, livestock or other animal food, cat litter,fertilizer, seeds, plant bulbs, rock salt, and foodstuffs.

Thus the several aforementioned objects and advantages are mosteffectively attained. Although preferred embodiments of the inventionhave been disclosed and described in detail herein, it should beunderstood that this invention is in no sense limited thereby and itsscope is to be determined by that of the appended claims.

1-50. (canceled)
 51. A closure for a package, including: a first profilewith a first upper portion and a first flange; a second profile with asecond upper portion and a second flange; and a connecting portionbetween the flanges, the connecting portion connected to one of theflanges by a separable connection that is more resistant to a sheerforce than to a peeling for when a load is placed on the closureassembly.
 52. The closure of claim 51 wherein the separable connectionis a first peel seal.
 53. The closure of claim 51 wherein a load on thefirst and second flanges is redirected away from the separableconnection to a location above the separable connection.
 54. The closureof claim 51 wherein the first and second flanges are attached to anexterior of respective first and second package walls.
 55. The closureof claim 51 wherein the first and second flanges are attached to aninterior of respective first and second package walls.